So I ended up figuring this issue out. When I installed the ArcObjects SDK one of the samples it installed was called "AddInEditorExtension." Even though this add-in was not installed it ArcMap acted as if it was. I actually had to go IN to the code and comment out the System.Windows.Forms.MessageBox.Show("Valid Feature"); inside of void Events_OnCreateChangeFeature(ESRI.ArcGIS.Geodatabase.IObject obj), because no matter what I did the message showed, even after I forcefully added the add-in and then removed it again. Thanks so much for your help on this. I had asked all the other users I know and checked websites and found no help until I saw your reply. You can imagine trying to copy in thousands of polygons into a feature class and getting that "Valid Feature" message on every single one. Instead of commenting the lines out as you suggested, I did a clean so there would be no files in the bin folder and the dll could not be used. It has worked so far.
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